chore: adds tests, clippy, formatting, and auditing to CI

changes the following to appease the new CI rules:
  * ignores unused dep warning for openssl-sys.
  * runs cargo +nightly fmt on source.
  * fixes clippy issues.
  * removes modules from V1 that weren't being used. These modules were behind v1
    feature flags that had been removed as well.
  * adds deny.toml from c2pa-rs.

deny.toml

@@ -0,0 +1,52 @@
+# Configuration used for dependency checking with cargo-deny.
+#
+# For further details on all configuration options see:
+# https://embarkstudios.github.io/cargo-deny/checks/cfg.html
+
+[graph]
+targets = [
+    { triple = "x86_64-unknown-linux-gnu" },
+    { triple = "x86_64-apple-darwin" },
+    { triple = "x86_64-pc-windows-msvc" },
+    { triple = "aarch64-apple-darwin" },
+    { triple = "wasm32-unknown-unknown" },
+]
+
+[advisories]
+yanked = "deny"
+
+ignore = [
+    "RUSTSEC-2021-0127", # serde_cbor
+    "RUSTSEC-2023-0071", # rsa Marvin Attack: (https://jira.corp.adobe.com/browse/CAI-5104)
+]
+
+[bans]
+multiple-versions = "allow"
+
+[licenses]
+allow = [
+    "Apache-2.0",
+    "BSD-2-Clause",
+    "BSD-3-Clause",
+    "CC0-1.0",
+    "ISC",
+    "LicenseRef-ring",
+    "MIT",
+    "MPL-2.0",
+    "Unicode-DFS-2016",
+    "Zlib",
+]
+confidence-threshold = 0.9
+
+[[licenses.clarify]]
+name = "ring"
+expression = "LicenseRef-ring"
+license-files = [
+    { path = "LICENSE", hash = 3171872035 }
+]
+
+[sources]
+unknown-registry = "deny"
+unknown-git = "deny"
+allow-registry = ["https://github.com/rust-lang/crates.io-index"]
+allow-git = []